CN116829111A

CN116829111A - Absorbent body with topsheet composite

Info

Publication number: CN116829111A
Application number: CN202180092833.3A
Authority: CN
Inventors: 叶逢春; G·埃德姆; 周松梅; 刘卉; C·斯普林加德-艾歇尔; L·迪吉罗拉莫-加拉索
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 2021-02-05
Filing date: 2021-02-05
Publication date: 2023-09-29
Also published as: WO2022165743A1; US20220249302A1; EP4288010A1; CN216222023U

Abstract

An absorbent body for an absorbent article, the absorbent body having a transverse direction and a longitudinal direction and having a thickness in a vertical direction perpendicular to the transverse direction and the longitudinal direction, the absorbent body comprising: 1) A wearer-facing first topsheet which is a water-permeable nonwoven layer comprising eccentric bicomponent fibers and has a basis weight of at least about 20gsm, preferably at least about 25 gsm; 2) A second topsheet disposed on the garment-facing side of the first topsheet, the second topsheet being a nonwoven layer comprising spunbond fibers and having a positive, preferably at least about 100%, more preferably at least about 400% cumulative unidirectional transmission index according to the national standard for the people's republic of China GB/T21655.2-2009, wherein the basis weight of the second topsheet is equal to or less than the basis weight of the first topsheet; 3) An absorbent core disposed on the garment-facing side of the secondary topsheet, and 4) a water-impermeable backsheet disposed on the garment-facing side of the absorbent core.

Description

Absorbent body with topsheet composite

Technical Field

The present invention relates to an absorbent body for an absorbent article such as a diaper having improved fluid handling characteristics.

Background

Absorbent articles for personal hygiene such as disposable diapers, disposable pants, adult incontinence undergarments and sanitary napkins are designed to absorb and contain body exudates, particularly urine, low viscosity fecal material and menstrual fluid (collectively referred to herein as "fluids"). These absorbent articles may comprise several layers providing different functions, such as a topsheet, a backsheet and an absorbent core arranged between the topsheet and the backsheet, among other layers.

The topsheet is generally liquid permeable and is configured to receive fluid and to help direct the fluid toward the absorbent core. Generally, the topsheet is a nonwoven fabric made of hydrophobic fibers and is made more hydrophilic by applying a hydrophilic surfactant treatment to its skin-facing surface so that fluid is attracted to the topsheet and then directed into the underlying layers. One of the important qualities of the topsheet is the ability to shorten the residence time of the fluid in the topsheet before the fluid can be absorbed by the absorbent core. Thus, one criterion for the quality of the topsheet is to reduce the amount of fluid retained on the topsheet, as well as the amount of time that fluid spends on the topsheet before being absorbed by the absorbent core. This can lead to various performance drawbacks if the fluid remains on the surface of the topsheet for too long. For example, fluid retained on the topsheet surface may migrate in response to movement of the wearer and cause leakage. The remaining fluid may cause a wet feel, discomfort, or even rash problem to the wearer.

To address the problem of long fluid residence on the topsheet, it has been proposed to provide, for example, apertures to allow faster fluid penetration, and/or three-dimensional deformation to reduce contact with the skin, such as those disclosed in PCT publication WO 2015/134359A. However, it has been found that while such treated topsheets may require additional expense, the benefits of increased fluid penetration may be less pronounced. Furthermore, in view of the recent consumer desire to use environmentally friendly products, there is a great pressure to use as little material as possible for absorbent articles. To meet such consumer demand, absorbent bodies made of less material and still having good fluid handling characteristics are desired.

Based on the foregoing, there is a need for absorbent articles having topsheets with improved fluid handling characteristics while maintaining softness performance and wear comfort. There is also a need for absorbent articles that can be manufactured economically.

Disclosure of Invention

The present invention relates to an absorbent body for an absorbent article, the absorbent body having a transverse direction and a longitudinal direction and having a thickness in a vertical direction perpendicular to the transverse direction and the longitudinal direction, the absorbent body comprising:

1) A first topsheet facing the wearer, the first topsheet being a water permeable nonwoven layer comprising eccentric bicomponent fibers and having a basis weight of at least about 20gsm, preferably at least about 25 gsm;

2) A second topsheet disposed on the garment-facing side of the first topsheet, the second topsheet being a nonwoven layer comprising spunbond fibers and having a positive, preferably at least about 100%, more preferably at least about 400% cumulative unidirectional transmission index according to the national standard for the people's republic of China GB/T21655.2-2009, wherein the basis weight of the second topsheet is equal to or less than the basis weight of the first topsheet;

3) An absorbent core disposed on the garment-facing side of the secondary topsheet, and

4) A water impermeable backsheet disposed on the garment-facing side of the absorbent core.

The invention also relates to an absorbent article comprising such an absorbent body.

Drawings

Fig. 1 is a schematic cross-sectional view of an embodiment of an absorbent body of the present invention, wherein the thickness (Z-direction) is exaggerated.

Fig. 2 is a perspective view of an exemplary absorbent article of the belt type.

Fig. 3 is a perspective view of an exemplary absorbent article of pant type.

Fig. 4A to 4C relate to the national standard of the people's republic GB/T21655.2-2009.

Definition of the definition

As used herein, the following terms shall have the meanings specified below:

"absorbent article" refers to an article that may be worn in the form of a belt diaper, pant diaper, incontinence pant, feminine hygiene undergarment, and the like. The "absorbent article" may be so configured as to absorb and contain various exudates discharged from the body, such as urine, feces, and menses. "absorbent article" may refer to a combination of articles suitable for use as an outer cover joined with a separate disposable absorbent insert for providing absorbent and containment functions, such as those disclosed in PCT publication WO 2011/087503A.

"longitudinal" refers to a direction extending substantially perpendicularly from one waist edge of the article to the opposite waist edge and generally parallel to the largest linear dimension of the article.

"transverse" refers to a direction perpendicular to the longitudinal direction.

"proximal" and "distal" refer to positions that are closer or farther, respectively, relative to the longitudinal center of the article.

"body-facing" and "garment-facing" refer to the relative position of an element or the relative position of a surface of an element or group of elements, respectively. "body facing" means that the element or surface is closer to the wearer than some other element or surface during wear. "garment-facing" refers to an element or surface that is farther from the wearer during wear than some other element or surface (i.e., an element or surface that is closer to the garment of the wearer, which may be worn on a disposable absorbent article).

By "disposed" is meant that the element is positioned at a particular location or position.

"joined" refers to such configurations: wherein one element is directly secured to another element by attaching the element directly to the other element; it also refers to such configurations: wherein an element is indirectly secured to another element by attaching the element to an intermediate member which in turn is attached to the other element.

"film" refers to a sheet-like material in which the length and width of the material far exceeds the thickness of the material. Typically, the film has a thickness of about 0.5mm or less.

"nonwoven", "nonwoven layer" or "nonwoven web" are used interchangeably to mean an engineered fibrous component that is predominantly planar, having been imparted with a designed level of structural integrity by physical and/or chemical means, but does not include weaving, knitting, or papermaking (ISO 9092:2019 definition). Oriented or randomly oriented fibers are bonded by friction and/or cohesion and/or adhesion. These fibers may be of natural or synthetic origin and may be staple or continuous filaments or fibers formed in situ. Commercially available fibers have diameters ranging from less than about 0.001mm to greater than about 0.2mm and they come in several different forms such as staple fibers (known as chemical staple fibers or chopped fibers), continuous filaments (filaments or monofilaments), untwisted bundles of continuous filaments (tows) and twisted bundles of continuous filaments (yarns). Nonwoven webs have been formed from many processes such as, for example, meltblowing processes, spunbonding processes, solution spinning, electrospinning, carding processes, and air laying processes. The basis weight of nonwoven webs is typically measured in grams per square meter (g/m ² Or gsm).

"Water-permeable" and "water-impermeable" refer to the permeability of a material within the intended use of a disposable absorbent article. In particular, the term "water permeable" refers to a layer or layered structure having pores, openings, and/or interconnected void spaces that allow liquid water, urine, or synthetic urine to pass through its thickness in the absence of a forcing pressure. Conversely, the term "water impermeable" refers to a layer or layered structure in which liquid water, urine, or synthetic urine cannot penetrate the thickness of the layer or layered structure in the absence of a forcing pressure (other than natural forces such as gravity). According to this definition, the water-impermeable layer or layered structure may be water vapor permeable, i.e., may be "vapor permeable".

"hydrophilic" describes the surface of a substrate that can be wetted by an aqueous fluid (e.g., aqueous body fluid) deposited on such substrates. Hydrophilicity and wettability are generally defined in terms of the contact angle and strike-through time of a fluid, such as through a nonwoven fabric. This is discussed in detail in the American Chemical Society publication entitled "Contact angle, wettability and Adhesion" (copyright 1964) by Robert F.Gould. When the contact angle between the fluid and the surface is less than 90 deg., or when the fluid tends to spread spontaneously along the surface of the substrate, it can be said that the surface of the substrate is wetted by the fluid (i.e., hydrophilic), both conditions often coexist. Conversely, a substrate is considered "hydrophobic" if the contact angle is greater than 90 ° and the fluid does not spontaneously spread along the surface of the fiber.

"extensibility" and "extensible" mean that the width or length of a component in a relaxed state can be extended or increased.

"elasticated" and "elasticized" refer to assemblies that include at least a portion made of an elastic material.

"extensible material", "extensible material" or "stretchable material" are used interchangeably and refer to the following materials: the material can be stretched to an elongation of at least about 110% of its relaxed initial length (i.e., to more than 10% of its initial length) without breaking or fracturing upon application of a biasing force and exhibits minimal recovery, i.e., less than about 20% of its elongation without complete breaking or fracturing upon release of the applied force, as measured by EDANA method 20.2-89. In the event that such an extensible material recovers at least 40% of its elongation upon release of an applied force, the extensible material will be considered "elastic" or "elastomeric". For example, an elastic material having an initial length of 100mm may extend at least up to 150mm and retract to a length of at least 130mm (i.e., exhibit 40% recovery) when the force is removed. An extensible material will be considered "substantially inelastic" or "substantially inelastic" in the event that the material does not recover 40% of its elongation upon release of the applied force. For example, an extensible material having an initial length of 100mm may extend at least to 150mm and retract to a length of at least 145mm (i.e., exhibit 10% recovery) when the force is removed.

Unless otherwise indicated, "size", "length", "width", "pitch", "diameter", "aspect ratio", "angle" and "area" of the article are measured in the following states: the article stretches to a fully stretched perimeter W1, which is measured according to the "fully article force values" herein and utilizes a ruler or small magnifying glass.

"artwork" refers to a visual representation that is viewable to the naked eye, which is provided by printing or other means, and has a color. Printing includes various methods and apparatus known to those skilled in the art, such as lithographic, screen, flexography, and gravure inkjet printing techniques.

As referred to herein, "color" or "colored" includes any primary color other than white, namely black, red, blue, violet, orange, yellow, green, and indigo, as well as any variation or mixture thereof. White is defined as those colors having an L value of at least 94, an a value equal to 0±2 and a b value equal to 0±2 according to the CIE L x a x b x color system.

Detailed Description

General description of the absorption body

The present invention relates to an absorbent body (20) for an absorbent article, the absorbent body (20) comprising a topsheet composite comprising a first topsheet and a second topsheet. FIG. 1 is a schematic cross-sectional view of an exemplary diaper absorbent body (20). Referring to cross-sectional view 1, the absorbent body (20) includes:

1) A first topsheet (36) facing the wearer, the first topsheet (36) being a water-permeable nonwoven layer comprising eccentric bicomponent fibers and having a basis weight of at least about 20gsm, preferably at least about 25 gsm;

2) A second topsheet (4) disposed on the garment-facing side of the first topsheet, the second topsheet being a nonwoven layer comprising spunbond fibers and having a positive, or at least about 100%, or at least about 400%, cumulative unidirectional transmission index according to the national standard for the people's republic of China GB/T21655.2-2009, wherein the basis weight of the second topsheet (4) is equal to or less than the basis weight of the first topsheet (36);

3) An absorbent core (28) arranged on the garment-facing side of the secondary topsheet (4), and

4) A water impermeable backsheet (38) disposed on the garment facing side of the absorbent core (28).

The components of the absorption body (20) may be directly and indirectly attached to each other, typically by gluing or thermal/pressure bonding. The wearer-facing first topsheet (36) and backsheet (38) may be attached to each other along their peripheries. Typically, adjacent layers will be bonded together by: conventional bonding methods are used, such as adhesive coatings, or thermal bonding, or pressure bonding, or combinations thereof, over the entire surface or a portion of the surface of the layer via slot coating or spraying. The bond between the components is not shown in fig. 1, except for the adhesive layers (71, 72) for clarity and legibility. Unless specifically mentioned otherwise, adjacent layers of the article should be considered as being attached to another layer. For example, the backsheet and the bottom cover of the absorbent core may typically be glued together. The adhesive used may be any standard hot melt adhesive as known in the art.

Referring to fig. 2, the absorbent article and absorbent body (20) of the present invention have a longitudinal axis LX extending in the longitudinal direction Y of the article, in a transverse direction X perpendicular to the longitudinal direction. Referring to fig. 1, the absorbent article and absorbent body (20) of the present invention have a thickness Z in a vertical direction perpendicular to the transverse direction and the longitudinal direction.

First top sheet

The first topsheet (36) of the present invention forms a wearer-facing surface and is a water permeable nonwoven layer comprising eccentric bicomponent fibers and having a basis weight of at least about 20gsm, or greater than about 20gsm, or at least about 25 gsm.

According to the measurements herein, the first topsheet (36) may have a "median absorption pressure" of less than about 6cm, or less than about 5 cm. The "median absorption pressure" according to the measurements herein is the "capillary suction height" at which the material has 50% of its "maximum equilibrium capillary adsorption capacity" during the absorption phase of the measurement process. "median absorption pressure" indicates the capillary capacity of the substrate layer. The first topsheet (36) has a relatively low "median absorption pressure" due to the high void volume of the eccentric fibers.

Without being bound by theory, the first topsheet (36) of the present invention provides a soft feel while also being compliant, soft feel, and non-irritating to the wearer's skin by having an eccentric microstructure and relatively high basis weight and high void volume. Furthermore, as discussed in further detail below, when combined with the second topsheet (4), liquid exudates that would otherwise remain in the first topsheet (36) are effectively discharged into the second topsheet (4) and further rapidly transported to the absorbent core (28) such that rewet from the first topsheet (36) is prevented, thus improving dryness on the wearer facing side of the first topsheet (36).

The eccentric bicomponent fibers may be selected from the group consisting of sheath-core, side-by-side, and islands-in-the-sea. The eccentric bicomponent fibers may be sheath-core with high levels of crimp. The first topsheet (36) may be substantially made of eccentric bicomponent fibers. Suitable first topsheets (36) may be made from a wide range of materials such as polyolefins and polyesters fibers and filaments, and may be spunbond, carded, wet-laid, meltblown, hydroentangled, or otherwise treated as known in the art. Exemplary suitable first nonwovens include breathable carded nonwovens having a polyester core or a polyolefin core and a polyolefin sheath. The polyester may be polyethylene terephthalate (PET). The polyolefin may be Polyethylene (PE) or polypropylene (PP). Natural fibers such as cotton, viscose or silk may be added.

The first topsheet (36) may have openings for enhanced dryness, or for delivering liquid breathability, softness, distribution or other benefits to the user. The opening of the first topsheet (36) may be at least about 0.12mm ² Or at least about 0.4mm in a minimum dimension, in an aesthetically pleasing shape and pattern.

The first topsheet (36) may have a plurality of grooves and a plurality of protrusions, wherein the difference between the grooves and the protrusions has a Z-direction height in the range of about 500 μm or more or about 500 μm to about 2000 μm. Due to this structure, the fluid can quickly move away from the wearer, providing a dry feel even after being wetted.

Second top sheet

The second topsheet (4) of the present invention is disposed on the garment-facing side directly below the first topsheet (36), the second topsheet (4) being a nonwoven layer comprising spunbond fibers, wherein the basis weight of the second topsheet (4) is equal to or less than the basis weight of the first topsheet. Furthermore, the secondary topsheet (4) has a rating for "textile-absorbent quick-drying properties" according to the national standard of the people's republic of China GB/T21655.2-2009, part 2: a positive, or at least about 100%, or at least about 400%, of the "cumulative one-way transfer index" of the dynamic moisture transfer method. Each of the first topsheet (36) and the second topsheet (4) may have a "maximum wetted radius immersion surface" according to the national standard for the republic of the China, GB/T21655.2-2009, wherein the maximum wetted radius immersion surface of the second topsheet (4) is less than the maximum wetted radius immersion surface of the first topsheet (36), or less than 50% of the maximum wetted radius immersion surface of the first topsheet, or less than 30% of the maximum wetted radius immersion surface of the first topsheet. The secondary topsheet (4) may have a maximum wetted radius of less than about 25mm or less than about 10mm. The difference in maximum wetted radius immersion surface between the first topsheet (36) and the second topsheet (4) may be at least about 5mm or at least about 10mm. A first topsheet (36) and a second topsheet Each of the sheets (4) may have a median absorption pressure as measured herein, wherein the median absorption pressure of the second topsheet (4) is higher than the median absorption pressure of the first topsheet (36). The difference in median absorption pressure between the first topsheet (36) and the second topsheet (4) may be at least about 0.5cmH ₂ O or at least about 1.0cm H ₂ O。

The "cumulative one-way transfer index" according to the national standard of the republic of China, GB/T21655.2-2009, is defined as the difference in cumulative moisture content between the top and bottom surfaces of the substrate layer over a unit test period, thus indicating how effectively moisture can pass through the substrate layer. Without being bound by theory, by having a positive cumulative unidirectional transfer index and a basis weight equal to or less than the first topsheet (36), the second topsheet (4) rapidly absorbs liquid exudates trapped within the crimped fibers in the first topsheet (36) by capillary effects, and then rapidly transfers the liquid exudates to the absorbent core (28) for containment. By so effectively discharging liquid exudates into the absorbent core (28), the primary topsheet (36) thus acts as a barrier between the absorbent core and the wearer, thereby preventing rewet by the wearer.

The "maximum wetted radius immersion surface" according to national standard for the people's republic of China, GB/T21655.2-2009, is defined as the maximum wetted ring at the top and bottom surfaces, wherein the slope of the water content is greater than the tan (15) of the top and bottom surfaces, respectively. The maximum wetting radius submersion according to the national standard of the people's republic of China, GB/T21655.2-2009, indicates how easily the substrate layer can be wetted. The "median absorption pressure" according to the measurements herein is the "capillary suction height" at which the material has 50% of its "maximum equilibrium capillary adsorption capacity" during the absorption phase of the measurement process. "median absorption pressure" indicates the capillary capacity of the substrate layer. Without being bound by theory, it is contemplated that by having the maximum wetted radius of the second topsheet (4) wetted with water less than the maximum wetted radius of the first topsheet (36) wetted with water, and having the median absorption pressure of the second topsheet (4) higher than the median absorption pressure of the first topsheet (36), liquid exudates are effectively discharged from the first topsheet (36) to the second topsheet (4), and further to the absorbent core (28).

Thus, the composite first and second topsheets of the present invention provide unexpected benefits, namely improved softness and dryness. The first topsheet and the second topsheet may be joined by bonding, embossing or ultrasonic bonding.

The secondary topsheet (4) may be hydrophilic and thus have a contact angle of less than 90 °. The second topsheet (4) may be SS, SSS, SM or SMS structured polyolefin, such as polypropylene (PP), and have a relatively low basis weight, for example, from about 5gsm to about 20gsm or less than about 20gsm, provided that the basis weight is not greater than the basis weight of the first topsheet (36).

Negative film

The absorbent body (20) of the present invention includes a water impermeable backsheet (38) disposed on the garment-facing side of the absorbent core (28). The backsheet (38) comprises a thin plastic film, such as a thermoplastic film having a thickness of less than about 0.10 mm. Exemplary backsheet films include those manufactured by headquarters in Richmond, VA, tredegar Corporation and sold under the trade name CPC2 film. Other suitable backsheet materials may include breathable materials that permit vapors to escape from the article while still preventing exudates from passing through the backsheet (38). The backsheet (38) may include a cover low basis weight nonwoven attached to the outer surface of the film to provide a softer feel.

Absorbent core

The absorbent body (20) of the present invention comprises an absorbent core (28) arranged on the garment-facing side of the secondary topsheet (4), which is sandwiched between the secondary topsheet (4) and the backsheet (38). The absorbent core comprises an absorbent material that can absorb and retain body fluids, particularly urine. The absorbent cores (28) according to the present invention are typically manufactured in the form of a continuous stream that can be stored and transferred, for example, as rolls of absorbent core material, and then individualized upon integration into an absorbent article such as a diaper. The absorbent core (28) has a majority of the absorbent capacity of the components of the absorbent article and comprises all or at least a majority of superabsorbent polymer (referred to herein as "SAP") particles.

The absorbent core (38) of the present invention may comprise a high loft material comprising superabsorbent polymer43). The term "high loft" refers to a low density, loose fabric as compared to a flat paper fabric. The high loft web is characterized by a relatively high porosity. This means that there is a relatively high amount of void space in which the superabsorbent polymer particles can be distributed. The high loft material of the present invention (without superabsorbent particles) may have a pressure of less than 0.20g/cm at a pressure of 4.14kPa (0.6 psi) ³ In particular at 0.05g/cm ³ To 0.15g/cm ³ Density in the range. The high loft layer (without superabsorbent particles) of the present invention may have a pressure of less than 0.20g/cm at 2.07kPa (0.3 psi) ³ In particular at 0.02g/cm ³ To 0.15g/cm ³ Density in the range. The high loft layer (without superabsorbent particles) of the present invention may have a pressure of less than 0.15g/cm at 0.83kPa (0.12 psi) ³ In particular at 0.01g/cm ³ To 0.15g/cm ³ Density in the range. The density can be calculated by dividing the basis weight of the high loft layer by its thickness measured at the corresponding pressure, as described below.

The high loft material (43) may comprise synthetic fibers, optionally mixed with natural fibers such as cellulose or cotton fibers or viscose fibers. The fibers may be made partially or completely from relatively elastic synthetic fibers, in Particular Polypropylene (PP), polyamide (PA, such as nylon) or polyethylene terephthalate (PET) fibers. The diameter of the fibers may be, for example, in the range of 0.01mm to 0.50 mm.

The high loft material (43) may specifically have a thickness of 0.30mm to 2.00mm or 0.50mm to 1.5mm, measured at a pressure of 4.14kPa (0.6 psi) and a basis weight of 15gsm to 500 gsm.

The high loft material (43) serves as a substrate for SAP particles 60, 62, which are at least partially distributed within their pores. SAP particles are typically deposited on one side of the high loft material (43) and are drawn into the high loft material (43), for example by gravity or negative pressure on the opposite side of the nonwoven. In this way, some particles remain close to the surface of the high loft material (43), and other generally smaller particles can penetrate deeper within the pores of the high loft nonwoven. SAP particles that are not trapped within the pores of the high loft layer but remain at the surface may be further immobilized by an adhesive layer (71) or (72). The high loft material (43) may be sandwiched between a top cover layer (41) and a bottom cover layer (42). The top cover layer (41) and the bottom cover layer (42) provide a cover on both sides of the intermediate layer for preventing SAP particles from falling off the high loft material (43) during the core and article manufacturing process and/or during use of the absorbent article. The absorbent core may furthermore comprise a wrapping layer (3) surrounding the high loft material (43) and the two cover layers (41, 42).

Alternatively, the absorbent core may comprise an absorbent layer with superabsorbent polymer, which is arranged between a first layer and a second layer of nonwoven material, which are fixed by a fibrous layer (not shown) of thermoplastic adhesive material. The first nonwoven layer and the second nonwoven layer may be relatively low basis weight nonwoven webs including synthetic fibers, monocomponent fibers such as PE, PET, and PP, multicomponent fibers such as side-by-side, core/sheath, or islands-in-the-sea fibers. Such synthetic fibers may be formed via a spunbond process or a meltblown process.

Other parts of the absorption body

The absorbent main body (20) may further comprise a liquid management layer 54 located directly under the secondary topsheet (4). The liquid management layer may also be referred to as a fluid acquisition layer or a fluid distribution layer. The function of such a layer is to acquire fluid from the topsheet rapidly away from the wearer facing side and/or to distribute it over a larger area so that it is more effectively absorbed by the absorbent core. Such a liquid management layer may also be placed between the backsheet and the absorbent core.

Alternatively, the absorbent body (20) may be free of any liquid management layer. In other words, the secondary topsheet (4) may be used as such an acquisition layer or distribution layer providing additional wrapping of the absorbent core (28) to avoid SAP particles from escaping beyond the core. The liquid management layer may be omitted as the first topsheet and the second topsheet simultaneously provide the function of rapidly transferring liquid exudates to the absorbent core (28) and preventing such transferred liquid from returning to the wearer-facing surface of the first topsheet (36). By the lack of a liquid management layer, the overall thickness of the absorbent body (20) can be kept relatively thin.

The absorbent body (20) for a diaper may also include features that improve the fit of the article around the legs of the wearer, particularly barrier leg cuffs (30) and gasketing cuffs (34). The barrier leg cuffs may be formed from a piece of material (typically a nonwoven) that is partially bonded to the remainder of the article and may be partially raised and thus upstanding from the plane defined by the first topsheet (36). The barrier leg cuffs are generally defined by a proximal edge joined to the rest of the article (typically the topsheet and/or backsheet), and a free end edge intended to contact the skin of the wearer and form a seal. The upstanding portion of the cuff typically includes an elastic element, such as one or more elastic strands (35). The barrier leg cuffs provide improved containment of liquids and other body exudates near the junction of the torso and legs of the wearer.

In addition to the barrier leg cuffs, the article may further comprise a gasketing cuff (34) formed in the same plane as the chassis of the absorbent body (20), which may in particular be at least partially enclosed between the topsheet or the barrier leg cuffs and the backsheet and may be placed laterally outward relative to the upstanding barrier leg cuffs. The gasketing cuff may provide a better seal around the thigh of the wearer. Typically each gasketing leg cuff will include one or more elastic bands or elements (33) that are included in the chassis of the diaper, such as between the topsheet and backsheet in the leg opening regions.

Application part

The absorbent body (20) of the present invention may be assembled with an applicator member for forming an absorbent article. Referring to fig. 2, the absorbent article may be a belt-type in which the application means is a fastening system comprising a pair of elongated members (190) and a receiving member (192), the elongated members (190) protruding laterally from the left and right side edges of the rear region of the absorbent body (20) and being capable of fastening with the receiving member (192) disposed on the front region. Alternatively, the elongate member (190) may protrude from the front region and be capable of fastening with a receiving member (192) on the rear region. The elongate member (190) can include an attachment portion, an extension portion, and a refastenable feature. The extension portion may be made of a highly stretchable laminate for receiving a stretching force upon application of the absorbent article, and the refastenable feature may be made of a material capable of physically engaging with the material of the receiving member (192). Combinations of materials for the refastenable feature and receiving member (192) include hook-and-loop, latch-and-hole, button-and-hole, hook-and-hole, low tack adhesive, and combinations thereof. The receiving member (192) may also have a protruding portion that may or may not be provided with refastenable features.

Referring to fig. 3, the absorbent article of the present invention may be of pant type, wherein the application means is an elastic belt (40) extending laterally from the front and back regions of the absorbent body (20), wherein the center of the front belt (84) is joined to the front waist panel of the absorbent body (20), the center of the back belt (86) is joined to the back waist panel of the absorbent body (20), the front and back belts (84, 86) each have a left side panel (82) and a right side panel (82), wherein the absorbent body (20) do not overlap, and are sewn to each other at a pair of lateral edges as side seams (32) to form a waist opening and two leg openings, each of the front belt (84) and the back belt (86) has laterally continuous proximal and distal edges (90, 88), the proximal edges (90) being positioned closer than the distal edges (88) to the longitudinal center of the article. The front and back belt (84, 86) may be formed of an inner sheet, an outer sheet, and a plurality of elastic bodies interposed therebetween and extending in the transverse direction.

Test method

All samples were conditioned at about 23 ℃ ± 2 ℃ and about 50% ± 2% relative humidity for 2 hours prior to testing.

National standard GB/T21655.2-2009 for the people's republic of China

Assessment of the moisture absorption and quick drying Properties of textiles

Part 2: dynamic moisture transfer method

1. Range of

The section GB/T21655 specifies a method for testing and evaluating the liquid water dynamic transfer properties of the moisture absorption and quick drying properties of textiles.

The part is suitable for various textiles and products thereof, and other products can be used for reference.

2. Normative reference file

The terms in the following documents are the terms of this section by reference to this section of GB/T21655. All subsequent revisions (excluding the content of the investigation) or revisions to the dated reference file are not applicable to the section; however, parties agreed upon in accordance with this section are encouraged to study whether the latest versions of these files are available. Where the reference file is not dated, its latest version is applicable to this section.

GB/T6529 textile-Standard atmosphere for humidity control and test (GB/T6529-2008,ISO 139:2005,MOD)

GB/T8629-2001 textile-household washing and drying procedure for test (equv ISO 6330:2000)

3. Terminology and definitions

The following terms and definitions apply to this part of GB/T21655.

3.1 soaking time T

The time required from the liquid contacting the fabric surface to the time the fabric begins to absorb moisture. The time required for the fabric to begin to absorb moisture is defined as the time when the slope of the first occurrence of the moisture content versus time curve is greater than or equal to tan15 deg..

3.2 Water absorption Rate A

Rate of increase of moisture content per unit time of fabric. The slope average value of the water content change curve is the average value of the slope of the water content change curve in the test time.

3.3 maximum wetting radius R

The fabric begins to wet to the maximum radius of the wetted area at the end of the specified time. In the moisture content curve, the maximum radius of the wetted area from the first occurrence of the slope of the curve being greater than or equal to tan15 ° to the end of the test time.

3.4 liquid Water diffusion Rate S

The cumulative transfer rate of liquid water in the radial direction when the fabric surface is wetted and then spread to the maximum wetted radius.

3.5 cumulative one-way transfer index O

The ability of moisture to pass from the soaking side of the fabric to the permeate side. Which is expressed as the ratio of the difference in water absorption on both sides of the fabric to the test time.

3.6 liquid Water dynamic Transmission Complex index M

Characterization of the overall properties of the liquid water in the fabric is dynamically transferred. Expressed as weighted values of the permeate side water absorption rate, the one-way transfer index, and the permeate side liquid water diffusion rate of the fabric.

4. Principle of

The fabric sample was placed horizontally. The liquid water spreads along the water-immersed surface of the fabric after contacting with the water-immersed surface thereof, and is transferred from the water-immersed surface to the permeate surface of the fabric while spreading on the permeate surface of the fabric. The water content is a function of time. After the test liquid is dripped into the water immersed by the test sample, the dynamic transmission condition of the liquid water is measured by a sensor closely contacted with the test sample, and a series of performance indexes are calculated, so that the performances of moisture absorption, quick drying, perspiration and the like of the textile are evaluated.

5. Apparatus and materials

5.1 liquid Water dynamic Transmission Performance tester

The appendix A shows the basic structural principle and requirements of the instrument, and instruments which can achieve the same effect can be used.

5.2 materials

Unless otherwise specified, all reagents should be analytically pure and water tertiary.

5.2.1 test solution: 9g/L sodium chloride (NaCl) solution.

6. Standard atmosphere for humidity control and test

6.1 Conditioning and test Standard atmosphere the standard atmosphere specified in GB/T6529 was used.

6.2 samples should be equilibrated in a relaxed state prior to testing. The method and the requirements for humidity regulation are regulated according to GB/T6529. The humidity is generally regulated for more than 16 hours, the synthetic fiber sample is at least 2 hours, and the sample with the official moisture regain of 0 does not need to be regulated.

7. Sampling and sample preparation

7.1 methods and amounts of sample collection were agreed upon by the product standard or by the parties involved. Cutting a full-width fabric with the width of more than 0.5m from each sample, and avoiding the matched end by more than 2m during sampling; the textile product takes at least 1 unit.

7.2 each sample was cut into two pieces, one for the pre-wash test and the other for the post-wash test. The washing method is carried out 5 times according to the procedure GB/T8629-2001 5A or according to the method and times agreed upon by the parties concerned. The washed sample is dried or naturally dried at a temperature of not more than 60 ℃.

7.3 five specimens before and after washing were cut out, respectively, and the specimen size was (90.+ -.1) mm× (90.+ -.1) mm. The samples should be evenly distributed in the area 150mm above the selvedge during cutting. Each sample was not in the same longitudinal and transverse position and avoided defects and wrinkles that affected the test results. If the product is made of different fabrics, the sample should be selected from the main functional areas.

7.4 any irregularities in the surface of the fabric will affect the detection result. If necessary, the sample may be ironed by a pressing method.

8. Test procedure

8.1.1 the corner of the sample to be measured is gently gripped with clean forceps and the sample is placed flat between the two sensors of the instrument. The side of the garment that is in close proximity to the body is usually placed as the water immersion surface in the direction of the dripping of the test liquid.

8.1.2 starting the instrument, dripping 0.2 g+/-0.01 g of test solution into the soaking water surface of the fabric in a specified time, and beginning to record the time and water content change condition. The test time is 120s, and the data acquisition frequency is not lower than 10Hz.

8.1.3 after the test is finished, taking out the sample, and automatically calculating and displaying the corresponding test result by the instrument.

8.1.4 the excess residual liquid on the sensor plate is sucked off with clean absorbent paper, left to stand for at least 1min, and no residual liquid should be ensured before retesting.

8.1.5 repeat steps 8.1.1 through 8.1.4 until 5 samples are tested.

9. Results calculation and rating

9.1 calculation

9.1.1 Water absorption Rate A

The average water absorption rate A of the immersed water surface is calculated according to the formula (1) _T And average water absorption rate A of tragic permeable surface _B The value is modified to about 0.1.

In the method, in the process of the invention,

a-average water absorption rate (divided into average water absorption A of immersed water _T And average water absorption rate A of permeation surface _B ) ,%/s; (if A)<0, taking a=0);

u-water immersion or penetration,%;

t is soaking time of a soaking surface or a penetrating surface, s;

t _p -water inlet time s;

U _i -the value of the water-cut or permeate surface water-cut curve at time i;

f-data sampling frequency.

9.1.2 liquid Water diffusion Rate S

The liquid water diffusion rate S is calculated according to the formula (2), and the value is modified to be about 0.1.

In the method, in the process of the invention,

s-liquid Water diffusion speed (divided into Water-soaking liquid Water diffusion speed S _T And the diffusion speed S of the liquid water of the permeation surface _B )，mm/s；

r _i -radius of test ring, mm;

t _i and t _i-1 -the time of liquid water from ring i-1 to ring i;

n-maximum number of test loops wetted by the water or permeate surface.

9.1.3 cumulative one-way transfer index O

The cumulative one-way transmission index O is calculated according to equation (3), and the value is modified to 0.1.

In the method, in the process of the invention,

o-cumulative one-way transfer index;

t-test time, s;

∫U _T -water absorption at the immersion level;

∫U _B -water absorption of the permeate side.

9.1.4 liquid water dynamic transmission comprehensive index M

The liquid water dynamic transmission comprehensive index M is calculated according to the formula (4), and the value is revised to be 0.01.

M ＝C ₁ A _BD +C ₂ O _D +C ₃ S _BD ················ (4)

C ₁ 、C ₂ And C ₃ Weight value (C) ₁ ＝0.25，C ₂ ＝0.5，C ₃ ＝0.25)。

A _BD 、O _D And S is _BD Is the water absorption rate of the permeation surface (A _B ) A unidirectional transmission index (O) and a permeation surface diffusion rate (S) _B ) Is calculated according to formulas (5) to (7):

when A is _BD 、O _D And S is _BD They are counted as 1 when 1 is not less than; when A is _BD 、O _D And S is _BD At 0 or less, they are counted as 0.

A _B,max 、A _B,min 、O _max 、O _min 、S _B,max And S is _B,min Is a constant, take A in Table 1 _B O and S _B Upper and lower limits of (2).

9.2 rating

The ratings were rated as required in table 1.

TABLE 1 performance index grading

10. Moisture absorption quick drying performance evaluation

The corresponding properties of the product can be assessed as indicated in Table 2, if desired. The corresponding properties before and after washing of the product reach the technical requirements of Table 2, and the product can be clearly shown as the product with the corresponding properties in the use instruction of the product.

Table 2 moisture absorption and quick drying Property specification of fabrics

11. Reporting

The test report should include the following:

a) The number of this section and the date of the test;

b) Sample description (name, number, raw material and main specification, etc.);

c) Washing procedures and times;

d) The name and model of the test instrument adopted;

e) Calculating the average value and the rating of the result in chapter 9, and reporting the standard deviation if necessary;

f) Reporting the assessment result of the moisture absorption quick-drying performance if required; and

g) Any deviations from the details of this section and any abnormalities in the test.

Appendix A (datay appendix) test principle and structure of sensor

A.1 principle of testing

A.1.1 schematic diagrams of instrument principle and structure are shown in fig. A.1 (fig. 4A of the present patent application) and fig. A.2 (fig. 4B of the present patent application).

A.1.2 7 concentric rings of test were placed on each of the upper and lower test sensor planes with a diameter of 58.4mm, and the resistance between each adjacent ring was continuously tested during the water diffusion of the test solution.

A.1.3 between every two adjacent rings, a voltage and a sampling resistor are applied. During the test, as moisture is centrally injected into the water surface of the textile, the moisture permeates and diffuses through the upper and lower surfaces of the textile. The voltage of the sampling resistor is continuously monitored, so that the water content data of the textile on the surface of the ring can be obtained.

A2 sensor Structure and composition

The test sensor is composed of an upper sensor probe, a lower sensor probe, a PCB, a water supply structure, a positioning structure and a counterweight part. The upper and lower sensors are the same ring size as in figure a.3 (figure 4C of the present patent application).

A.3 sensor specification

A.3.1 upload sensor:

-consisting of probes in spring communication, seven test rings (figure a.3), ring zone distance 5mm±0.05mm;

-spring probe gauge: the diameter of the contact surface is 0.54mm plus or minus 0.02mm, and the copper is gold-plated.

A.3.2 lower sensor:

the probe consists of communicated probes, wherein the distance between seven test rings and the ring area is 5mm plus or minus 0.05mm;

-probe gauge: the diameter of the contact surface is 1.2mm plus or minus 0.02mm, and the copper is plated with gold; the resistance is <50mΩ.

A.4 test liquid conveying system

The technical parameters of the test liquid conveying system are as follows:

-time of liquid delivery: 20s;

-delivering the liquid volume: 0.2g + -0.01 g;

-a transport liquid outlet: the "0" ring of the upper sensor;

-delivery fluid outlet specification: the inner diameter of the stainless steel tube is 0.5mm.

A5 calibration and calibration of instruments

The technical parameters of instrument calibration and calibration are as follows:

standard test solution conductivity: 16mS + -0.1 mS;

test fluid delivery: 0.2g + -0.01 g;

-water inlet time: 20s;

-test time: 120s;

test head pressure: 4.65 N.+ -. 0.05N (475 gf.+ -. 5 gf).

Capillary adsorption test method

The "capillary sorption test method" is used to determine the sorption and desorption behavior of the porous material, and in particular the median sorption pressure. The method utilizes a stepwise controlled pressure differential and measures the movement of the associated fluid into and out of the porous sample. The Median Absorption Pressure (MAP) is the pressure differential at which the material has 50% of its maximum Normalized Capillary Fluid Absorption (NCFA) during the absorption phase of the measurement, and is measured as cmH ₂ O represents.

Principle of the method

For a uniform cylindrical bore, the radius of the bore is related to the pressure differential required to fill or empty the bore by the following formula

Differential pressure = (2γcos Θ)/r,

where γ=liquid surface tension, Θ=contact angle, and r=pore radius.

The pores contained in natural and man-made porous materials are often referred to by terms such as voids, pores, or conduits, and these pores are often not entirely cylindrical nor entirely uniform. However, the above formula can be used to relate the pressure differential to the effective pore radius and characterize the effective pore radius distribution in the porous material by monitoring the movement of liquid into or out of the material as a function of the pressure differential. (since the use of an effective pore radius approximates a non-uniform pore as a uniform pore), the results produced by this general method may not be exactly consistent with measurements of void size obtained by other methods (e.g., microscopy).

Capillary adsorption test methods utilize the principles described above and use "liquid porosimetry" as published by b.miller and i.tyomkin at The Journal of Colloid and Interface Science (1994), volume 162, pages 163-170: new method and application (Liquid Porosimetry: new Methodology and Applications), "the capillary sorption test method was applied to practice, and this document is incorporated herein by reference. This method relies on measuring the increase in volume of liquid flowing into or out of the porous material as the air pressure differential between the ambient ("laboratory") air pressure and the slightly elevated air pressure (positive pressure differential) surrounding the sample in the sample testing chamber varies. The sample is introduced into the dried sample chamber and the sample chamber is controlled to a positive pressure differential (relative to the laboratory) sufficient to prevent ingestion of fluid into the sample after the fluidic bridge is opened. After opening the fluid bridge, the air pressure difference is reduced to 0 in step, and in the process, a subset of the pores collect liquid according to their effective pore radius. After reaching a minimum pressure differential at which the mass of fluid within the sample is at a maximum, the pressure differential is again stepped up toward the starting pressure and liquid is drained from the sample. During the absorption sequence (from maximum differential pressure or minimum corresponding effective pore radius to minimum differential pressure or maximum corresponding effective pore radius), the fluid absorption (g/g) of the sample absorbed at each differential pressure is determined in the method. After correcting for any fluid movement for each particular pressure step measured on the empty chamber, the sample fluid absorption (g/g) for each pressure step is determined by dividing the equilibrium amount (g) of absorption liquid associated with that particular step by the dry weight (g) of the sample.

Sample conditioning and sample preparation

The capillary sorption test method was performed on samples that had been conditioned in a chamber having a temperature of 23 ℃ ± 2.0 ℃ and a relative humidity of 50% ± 5%, all under the same environmental conditions and in such conditioning chamber. Any damaged product or sample having defects such as wrinkles, tears, holes, etc. was not tested. For the purposes of the present invention, a sample conditioned as described herein is considered a dry sample. Three samples were measured for any given tested material and the results from those three duplicate samples were averaged to give the final reported value. Each of the three replicate samples has a diameter of 50 mm.

Apparatus and method for controlling the operation of a device

Apparatus suitable for use in this method are described in "liquid porosimetry" published by B.Miller and I.Tyomkin at The Journal of Colloid and Interface Science (1994), volume 162, pages 163-170: new methods and applications (Liquid Porosimetry: new Methodology and Applications) ". In addition, a pressure control of the sample chamber at 0mmH can be used ₂ O and 1200mmH ₂ Any pressure control scheme between the differential pressures of O replaces the pressure control subsystem described in this reference. One example of a suitable integral instrument and software is a TRI/automatic porosimeter ((Textile Research Institute (TRI)/Princeton Inc (Princeton, n.j., u.s.a.))) which is an automated computer-controlled instrument for determining pore volume distribution in porous materials (e.g., volumes of different sized pores in the range of 1 μm to 1000 μm effective pore radius), a computer program such as automated instrument software version 2000.1 or 2003.1/2005.1 or 2006.2, or a data processing software version 2000.1 (available from tricanceton Inc.) and a spreadsheet program can be used to capture and analyze measured data.

Method program

The wetting liquid used was a degassed 0.9% NaCl solution. The density of the liquid is 1.01g/cm ³ The surface tension γ was 72.3±1mN/m, and the contact angle cos Θ=0.37. A 90-mm diameter hybrid-cellulose-ester filter membrane (such as a membrane of Millipore Corporation (Bedford, MA), catalog # RAWP 09025) with a characteristic pore size of 1.2 μm was attached to the porous frit of the sample chamber (Monel plate, 90mm diameter, 6.4mm thickness, from Mott corp. (F)armington, CT), or equivalent).

It is known to those skilled in the art that it is critical to degas the test fluid as well as the frit/membrane/tube system, which leaves the system free of bubbles.

A metal weight weighing 414g was placed on top of the sample to apply a constant confining pressure of 2.068kPa during the measurement.

The differential pressure (in mmH ₂ The order of O) is as follows: 800. 400, 380, 360, 340, 320, 300, 280, 265, 250, 235, 220, 205, 190, 175, 160, 145, 130, 115, 100, 90, 80, 70, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80, 90, 100, 115, 130, 145, 160, 175, 190, 205, 220, 235, 250, 265, 280, 300, 320, 340, 360, 380, 400, 800.

The criteria for moving from one pressure step to the next is that the sample measured fluid absorption/drainage is less than 10mg/min for 15s.

By following this procedure for an empty sample cell, a separate "blank" measurement is made in the absence of sample or weight on the membrane/frit assembly. Any observed fluid movement (g) was recorded at each pressure step. Fluid absorption/retention data of the sample is calibrated for any fluid movement associated with an empty sample chamber by subtracting the fluid absorption/retention value of the "blank" measurement from the corresponding value in the sample measurement.

Determination of Median Absorption Pressure (MAP)

As described above, for each of the three samples, the capillary fluid (g) absorbed by each sample during its absorption cycle was corrected for any effect of the empty chamber and then divided by the dry mass of the sample to obtain an absorbed capillary fluid normalized by the dry sample mass in g/g. This is NFCA. NCFA is given in g/g and is calculated for each differential pressure step. NFCA is the cumulative parameter. For example, on the absorption portion of the pressure sequence, at 300mmH ₂ The NFCA value at O is already at 800mmH ₂ O and 300mmH ₂ O is absorbed between and as such for all other points of total fluid (in g/g). Maximum NCFA of fluid absorption of 0mmH ₂ NCFA value at O.

The Median Absorption Pressure (MAP) is the pressure difference at which the material has 50% of its maximum NCFA in the measured fluid absorption portion (the first half of the specified pressure sequence), and is measured as mmH ₂ O represents. If the NFCA value for any pressure step in the pressure sequence is not exactly 50%, then linear interpolation is performed between two adjacent pressures (one above the other) where NFCA spans 50% to derive the MAP for the particular sample.

Calculating an arithmetic average of three values of MAP for three samples and subtracting it from mmH ₂ Conversion of the pressure units of O to cmH ₂ Units of O, and recorded as cmH ₂ O is the unit of the overall parameter MAP.

Thickness and density measuring method

The method is used to measure the thickness (caliper) of the high loft material (43) in a standardized manner. The density can then be calculated from the thickness and basis weight of the layer. Unless otherwise indicated, thickness and density are indicated for a high loft material in the absence of SAP particles. The measurement should preferably be made on the high loft material before it is converted into an absorbent core and is thus SAP free. If the raw material is not available, the high loft material (43) may be obtained by carefully taking out from the absorbent core and removing most of the SAP particles (e.g. by careful shaking or suction). The freeze spray may be used to separate the intermediate layer from other layers. The samples should be kept at 21 ℃ ± 2 ℃ and 50% ± 10% RH for at least 24 hours to reach equilibrium, especially if they have been previously compressed.

The device comprises: a Mitutoyo manual calliper gauge with 0.01mm resolution, or equivalent instrument.

Contact pin: circular flat feet with a diameter of 16.0mm (+ -0.2 mm). A circular weight may be applied to the foot (e.g., a slotted weight to facilitate application about the instrument axis) to achieve the target weight. The total weight of the foot and added weight (including shaft) is selected to provide the desired pressure to the sample, for example, a pressure of 4.14kPa (0.6 psi). The thickness can be determined under different pressures using corresponding different weights applied to the foot. The thickness and density measurements indicate the applied pressure, for example, measured at 4.14kPa (0.6 psi) or 1.2 kPa.

The callipers were mounted with the lower surface of the contact foot in the horizontal plane, such that the lower surface of the contact angle contacted the center of the flat horizontal upper surface of the substrate of about 20cm x 25 cm. With the contact angle resting on the substrate, the gauge length is set to read zero.

Ruler: calibration metal scale with mm as scale.

Stopwatch: the accuracy was 1 second.

Sample preparation: the center layer was conditioned for at least 24 hours as indicated above.

Measurement protocol: the layers are flattened against the bottom side, i.e. the side is intended to be placed towards the backsheet in the finished product facing downwards. The measurement points, i.e. the middle of the sample, are carefully drawn on the top side of the layer, taking care not to compress or deform the layer. In the unlikely case that the high loft nonwoven layer is not uniform in the transverse direction or the longitudinal direction, these values are measured at the center of the sample corresponding to the center of the absorbent core to be made from the sample.

The contact foot of the gauge is raised and the middle layer is placed flat on the base plate of the gauge with the top side of the core up so that when lowered, the center of the foot is on the marked measurement point.

The foot was gently lowered onto the sample and released (ensuring the scale was "0" before starting the measurement). The thickness values were read 10 seconds after releasing the foot to the nearest 0.01mm.

The procedure is repeated for each measurement point. Ten samples were measured in this way for a given material and the average thickness was calculated and recorded with an accuracy of one tenth of a mm. The basis weight of each sample was calculated by dividing the weight of each sample by their area.

In g/cm ³ Density in units is determined by measuring the basis weight (in g/cm ² Unit) divided by the thickness (in cm).

Examples

Examples 1-3 and comparative examples 1-2 having the following first topsheet and second topsheet combinations as shown in table 3 were provided, and some were subjected to the measurements described above, and their results are provided in table 4.

TABLE 3 Table 3

TABLE 4 Table 4

The composite first and second topsheets of examples 1-3, which meet the parameter requirements of the present invention, provide improved fluid handling properties while maintaining softness properties and wearing comfort when formed into an absorbent body.

Example 1, example 3 and comparative example 1 were formed as pant-type absorbent articles, all of which had the same structural elements except for the topsheet composite as described above. The exemplary article was tested using a curved global acquisition method and a soft touch dryness (cGAM-LTD) test, which are an internal method for measuring the time required to acquire three consecutive 75ml brine surges, and measuring the rewet of the diaper at low rewet pressure (0.03 psi) using absorbent paper after each surge. The lower the time cGAM of the different gushes, the lower the weight of the LTD value is advantageous. The results of this test are summarized in table 5.

TABLE 5

	Example 1	Example 3	Comparative example 1
				cGAM inrush current 1(s)	75	79	78
cGAM inrush current 2(s)	265	293	269
				LTD rewet/g at time 2	0.076	0.067	0.138

Example 1 and comparative example 2 were formed into a belt-type absorbent article having a similar structure, except that the topsheet composite was as specified above, and the composition of the SAP was used in the absorbent core as described below.

Example 1:6.98g BASF N7059 and 6.30g NS L825。

Comparative example 2:7.01g BASF N7059 and 7.01g BASF N7059。

60 panelists were recruited as caregivers to use infants of size 4 (L) weighing 9kg-14kg, who were approximately equal numbers of boys and girls, and had a mixed use experience of the primary brand with a similar price range. Each panelist was required to use 5 different sequences of test samples, 3 days each, and provided enough samples to test each test sample. The 5 test samples are example 1 and comparative example 2. Panelists were asked to record the number of urine and fecal leakage events. The percent leakage is provided in table 6.

TABLE 6

Value of	Example 1	Comparative example 2
			Number of urine change samples	1011	997
Percent urine leakage (%)	0.3％	0.8％
			Number of fecal replacement samples	283	270
Percent fecal leakage (%)	0.0％	1.1％

Example 1 provides a statistically significantly smaller percentage of urine and fecal matter leakage at a 95% confidence level than comparative example 2, despite having a smaller amount of SAP in the absorbent core.

The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Rather, unless otherwise indicated, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as "40mm" is intended to mean "about 40mm". Furthermore, each numerical range given throughout this specification includes every narrower numerical range that falls within such broader numerical range.

Each document cited herein, including any cross-referenced or related patent or application, is incorporated by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to the present invention, or that it is not entitled to any disclosed or claimed herein, or that it is prior art with respect to itself or any combination of one or more of these references. Furthermore, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims

1. An absorbent body for an absorbent article, the absorbent body having a transverse direction and a longitudinal direction and having a thickness in a vertical direction perpendicular to the transverse direction and the longitudinal direction, the absorbent body comprising:

2. The absorbent body of claim 1, wherein each of the first topsheet and the second topsheet has a maximum wetted radius of water surface according to the national standard for the republic of the people, GB/T21655.2-2009, and the maximum wetted radius of water surface of the second topsheet is less than the maximum wetted radius of water surface of the first topsheet, preferably less than 50% of the maximum wetted radius of water surface of the first topsheet, more preferably less than 30% of the maximum wetted radius of water surface of the first topsheet.

3. The absorbent body of claim 2 wherein the secondary topsheet has a maximum wetted radius water soak of less than about 25mm, preferably less than about 10mm, according to the national standard of the people republic of China GB/T21655.2-2009.

4. The absorbent body of any of the preceding claims, wherein each of the first topsheet and the second topsheet has a median absorption pressure according to the capillary sorption test method herein, and the median absorption pressure of the second topsheet is higher than the median absorption pressure of the first topsheet.

5. The absorbent body of claim 4, wherein the first topsheet has less than about 6cmH as measured herein ₂ O, preferably less than about 5cmH ₂ Median absorption pressure of O.

6. The absorbent body of any of the preceding claims, wherein the bicomponent fibers used to make the first topsheet are selected from the group consisting of sheath-core, side-by-side, and islands-in-the-sea.

7. The absorbent body set forth in claim 6 wherein the first topsheet is a breathable carded nonwoven having a polyester core or a polyolefin sheath.

8. The absorbent body of any of the preceding claims, wherein the secondary topsheet has a contact angle of less than 90 °.

9. The absorbent body of any of the preceding claims, wherein the absorbent core comprises a high loft material comprising superabsorbent polymer.

10. The absorbent body of claim 9, wherein the absorbent body is free of a liquid management layer.

11. The absorbent body according to any one of claims 1 to 8, wherein the absorbent core comprises an absorbent layer comprising superabsorbent polymer, the absorbent layer being disposed between a first layer and a second layer of nonwoven material secured by a fibrous layer of thermoplastic adhesive material.

12. The absorbent body of any of the preceding claims, wherein the first topsheet is apertured.

13. An absorbent article comprising an application member and an absorbent body according to any of the preceding claims, wherein the application member is selected from the group consisting of a fastening member and an elastic belt.

14. An absorbent body for an absorbent article, the absorbent body having a transverse direction and a longitudinal direction and having a thickness in a vertical direction perpendicular to the transverse direction and the longitudinal direction, the absorbent body comprising:

1) A wearer-facing first topsheet which is a water-permeable nonwoven layer comprising eccentric bicomponent fibers and has a basis weight of greater than 20 gsm;

2) A second topsheet disposed on the garment facing side of the first topsheet, the second topsheet being a nonwoven layer comprising spunbond fibers and having a basis weight of less than 20 gsm;

15. The absorbent body set forth in claim 14 wherein the bicomponent fibers used to make the first topsheet are selected from the group consisting of sheath-core, side-by-side, and islands-in-the-sea.

16. The absorbent body set forth in claim 15 wherein the first topsheet is a breathable carded nonwoven having a polyester core or a polyolefin sheath.

17. The absorbent body of any one of claims 14 to 16, wherein the absorbent core comprises a high loft material comprising superabsorbent polymer.

18. The absorbent body of claim 17, wherein the absorbent body is free of a liquid management layer.

19. The absorbent body set forth in any one of claims 14 to 16 wherein the absorbent core comprises an absorbent layer comprising superabsorbent polymer disposed between a first layer and a second layer of nonwoven material held by a fibrous layer of thermoplastic adhesive material.

20. The absorbent body of any one of claims 14 to 19, wherein the first topsheet is apertured.

21. An absorbent article comprising an application member and an absorbent body according to any one of claims 14 to 20, wherein the application member is selected from the group consisting of a fastening member and an elastic belt.